the nitroreductase. The maxicell technique was used to identify the nitroreductase and its molecular weight was estimated as. 28KDa, which is close to the ...
Nucleotide sequence of Salmonella typhimurium nitroreductase gene Masahiko Watanabe, Motoi Ishidate Jr and Takehiko Nohmi Division of Genetics and Mutagenesis, Biological Safety Research Center, National Institute of Hygienic Sciences, 1-18-1, Kamiyoga, Setagaya-ku, Tokyo 158, Japan EMBL accession no. Xl 7250
Submitted January 5, 1990
'Classical nitroreductase' is an enzyme involved in the intracellular metabolic activation of mutagenic nitroarenes (1). We have already cloned the nitroreductase gene of Salmonella typhimurium TA1538 (2) and determined the nucleotide sequence by dideoxy sequence analysis of both strands. Below is shown the nucleotide sequence of 1690 base fragment which contains an open reading frame of 651 nucleotides with potential to encode the nitroreductase. The maxicell technique was used to identify the nitroreductase and its molecular weight was estimated as 28KDa, which is close to the calculated molecular weight of 23,955. Possible sequence of -35, -10, S.D. and rhoindependent transcriptional termination signal are indicated.
ACKNOWLEDGEMENT Supported by a grant-in-aid from the Japan Health Sciences Foundation.
REFERENCES 1. Rosenkranz,H.S. and Mermelstein,R. (1983) Mutat. Res. 114, 217-267. 2. Watanabe,M. et al. (1989) Mutat. Res. 216, 211-220.
GATC~CGCCCAAGTCGCCTGGTAAATCAAAAC'TTTACCGCAGCA±.Z~
AI'TACAACcGrccGAA
(-10)
(-35)
90 180 270
AAGGGTACrACACAGGAAGAAZ3 ±±±.& AAOcA¶~ArAGGIJAcCGMA M D I V S V A L Q R Y S T K A F D P S K K (SD)
360
ACTGACcCGAAGGAAATAACCArCGAACCACCA2CGCCC'TT''G L T A E E A D K I K T L L Q Y S P S S T N S Q P W H F I V A A C AS~)AGAcGAAEc[GoGc1cC¶Q CAAGGGAGcAGGGGAG cM[ccxcGAATA S T E E G K A R V A K S A A G N Y T F N E R K M L D A S H V
450
V V F C A K T A M D D A W L
GGAAGCTAAAGCSGCAAATATAAA±Z3.± E A K A A N D
K G
R
R
F
F
E R V V D Q
A D
M
H R V
S
E D L
A D
K D
540
X CZAGCSCA___630 G R F A T P
D H Q W M A K
720
GCAGGTTrATCTAACGTGCAATC¶-1xGGCGCKOGCGOUsA¶EGGGAcrGcCSCXCCAAGTS1AIGTcGA0GCCGAGGr 810 Q V Y L N V G N F L L G V A A M G L D A V P I E G F D A E V E ±FVGGAKAEAGGCTYTACT A GcGGCVAPV GAHAGHGAGGAVETDFANA L D A